Package g2401_2500.s2485_find_the_pivot_integer

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    2485 - Find the Pivot Integer\.

    Easy

    Given a positive integer n, find the pivot integer x such that:

    • The sum of all elements between 1 and x inclusively equals the sum of all elements between x and n inclusively.

    Return the pivot integer x. If no such integer exists, return -1. It is guaranteed that there will be at most one pivot index for the given input.

    Example 1:

    Input: n = 8

    Output: 6

    Explanation: 6 is the pivot integer since: 1 + 2 + 3 + 4 + 5 + 6 = 6 + 7 + 8 = 21.

    Example 2:

    Input: n = 1

    Output: 1

    Explanation: 1 is the pivot integer since: 1 = 1.

    Example 3:

    Input: n = 4

    Output: -1

    Explanation: It can be proved that no such integer exist.

    Constraints:

    • 1 <= n <= 1000

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Integer pivotInteger(Integer n)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait